XRP7720 Datasheet, PDF (13/28 Pages) Exar Corporation – Quad Output Universal Customizable PMIC with PFM

XRP7720
Quad Output Universal Customizable PMIC with PFM
FUNCTIONAL OVERVIEW
The XRP7720 is a quad-output digital pulse
width modulation (DPWM) controller with
integrated gate drivers for use with
synchronous buck switching regulators. Each
output voltage can be programmed from 0.6V
to 5.5V without the need for an external
voltage divider. The wide range of
programmable DPWM switching frequency
(from 105 kHz to 1.2 MHz) enables the user to
optimize for efficiency or component sizes.
Since the digital regulation loop requires no
external passive components, loop
performance is not compromised due to
external component variation or operating
condition.
The XRP7720 provides a number of critical
safety features, such as Over-Current
Protection (OCP), Over-Voltage Protection
(OVP), Over Temperature Protection (OTP)
plus input Under Voltage Lockout (UVLO). In
addition, a number of key health monitoring
features including warning level flags for the
safety functions and various Power Good
(PGOOD) functions which may be configured
to the GPIOs for hardware monitoring. The
above are all programmable during the
development phase through PA 5.1 when
using the XRP7720ILB-DEV.
For hardware communication, the XRP7720
has two logic level General Purpose Input-
Output (GPIO) pins, three 15V, open drain,
Power System Input-Output (PSIO) pins, and
an ENABLE pin. Two pins are dedicated to the
SMBus data (SDA) and clock (SCL) which are
available in the XRP7720ILB-DEV but are
eliminated in the production version. If full
dynamic control and telemetry are desired in
the production system, the pin compatible
XRP7724 is available.
In addition to providing four switching outputs,
the XRP7720 also provides a stand-by linear
regulator that produce 5V for a total of 5
customer usable supplies in a single device.
The 5V LDO is used for internal power and is
also optionally available to power external
circuitry. There is also a 1.8V linear regulator
which is for internal use only and should not
be used externally.
A key feature of the XRP7720 is its powerful
power management and time to market
capabilities through the use of the
XRP7720ILB-DEV. During development, all
four outputs are independently programmable
which provides full control of the delay, ramp,
and sequence during power up and power
down. Additionally, this programmability
allows control of the interaction of the outputs
and power down in the event of a fault,
including active ramp down of the output
voltages to remove an output voltage as
quickly as possible. The outputs may also be
defined and controlled as groups.
The XRP7720ILB-DEV and standard
XRP7720ILB-XXXX-F provide two different
types of programmable memory. The
XRP7720ILB-DEV has a rewritable Non-Volatile
Flash Memory (NVFM) that allows multiple re-
configurations during development. In
production, the XRP7720ILB-XXXX-F is factory
programmed in a one-time programmable
memory.
The XRP7720 brings an extremely high level of
functionality and performance to a
programmable power system.
Ever
decreasing product budgets require the
designer to quickly make good
cost/performance tradeoffs to be truly
successful. By incorporating four switching
channels, an LDO, and internal gate drivers in
a single package, the XRP7720 allows for
extremely cost effective power system
designs. The key cost factor to consider in
cost tradeoffs is the flexibility of the
XRP7720ILB-DEV during systems reliability
testing. The programmable versatility of the
XRP7720ILB-DEV along with the lack of hard
wired and on board configuration components
allows for minor and major changes during
development to be made in circuit and on the
board, by simply reprogramming with PA 5.1.
© 2014 Exar Corporation
13/28
Rev. 1.0.0